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‘Who's who’ in renal sphaerosporids (Bivalvulida: Myxozoa) from common carp, Prussian carp and goldfish – molecular identification of cryptic species, blood stages and new members of Sphaerospora sensu stricto

Published online by Cambridge University Press:  24 August 2012

ASTRID SIBYLLE HOLZER ,
P. BARTOŠOVÁ ,
H. PECKOVÁ ,
T. TYML ,
S. ATKINSON ,
J. BARTHOLOMEW ,
D. SIPOS ,
E. ESZTERBAUER  and
I. DYKOVÁ
ASTRID SIBYLLE HOLZER*
Affiliation:
Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic, 37005 České Budějovice, Czech Republic
P. BARTOŠOVÁ
Affiliation:
Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic, 37005 České Budějovice, Czech Republic
H. PECKOVÁ
Affiliation:
Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic, 37005 České Budějovice, Czech Republic
T. TYML
Affiliation:
Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic, 37005 České Budějovice, Czech Republic Faculty of Science, University of South Bohemia, 37005 České Budějovice, Czech Republic
S. ATKINSON
Affiliation:
Department of Microbiology, Oregon State University, Corvallis, OR 97331, USA
J. BARTHOLOMEW
Affiliation:
Department of Microbiology, Oregon State University, Corvallis, OR 97331, USA
D. SIPOS
Affiliation:
nstitute for Veterinary Medical Research, Centre for Agricultural Research, Hungarian Academy of Sciences, 1143 Budapest, Hungary
E. ESZTERBAUER
Affiliation:
nstitute for Veterinary Medical Research, Centre for Agricultural Research, Hungarian Academy of Sciences, 1143 Budapest, Hungary
I. DYKOVÁ
Affiliation:
Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic, 37005 České Budějovice, Czech Republic Department of Botany and Zoology, Faculty of Science, Masaryk University, 61137 Brno, Czech Republic
*
*Corresponding author: Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic, Branišovská 31, 37005 České Budějovice, Czech Republic. Tel: +420 38777 5424. Fax: +420 38 5310388. E-mail: astrid.holzer@paru.cas.cz
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Summary

Myxozoans are a group of diverse, spore-forming metazoan microparasites bound to aquatic environments. Sphaerospora dykovae (previously S. renicola) causes renal sphaerosporosis and acute swim bladder inflammation (SBI) in juvenile Cyprinus carpio carpio, in central Europe. A morphologically similar species with comparably low pathogenicity, S. angulata has been described from C. c. carpio, Carassius auratus auratus and Carassius gibelio. To clarify uncertainties and ambiguities in taxon identification in these hosts we decided to re-investigate differences in spore morphology using a statistical approach, in combination with SSU and LSU rDNA sequence analyses. We found that developing spores of S. angulata and S. dykovae cannot be distinguished morphologically and designed a duplex PCR assay for the cryptic species that demonstrated S. dykovae is specific to C. c. carpio, whereas S. angulata infects C. a. auratus and C. gibelio. The molecular identification of myxozoan blood stages in common carp and goldfish, which had previously been ascribed to Sphaerospora spp. showed that approximately 75% of blood stages were from non-sphaerosporid coelozoic species infecting these cyprinids and more than 10% were from an alien species, Myxobilatus gasterostei, developing in sticklebacks. We hereby report non-selective myxozoan host invasion and multi-species infections, whose role in SBI still requires clarification.

Keywords

SphaerosporaMyxozoacyprinidmorphometrycryptic speciationribosomal DNAmolecular identificationblood stagesmulti-species infection
Type
Research Article
Information
Parasitology , Volume 140 , Issue 1 , January 2013 , pp. 46 - 60
Copyright
Copyright © Cambridge University Press 2012

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